DNA

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DNA

• Structure/Function

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RECALL

• 4 classes of macromolecules
• Carbohydrates
• Lipids
• Proteins
• NUCLEIC ACIDS!!!
• Subunit NUCLEOTIDES

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• Nucleic Acid Examples
• DNA deoxyriboNUCLEIC ACID
• (de without, oxy oxygen, ribo ribose
  sugar)
• Store and pass genetic information
• RNA riboNUCLEIC ACID
• Protein synthesis
• Subunits of DNA/RNA nucleotides

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DNA

• Very long thin molecule made up of linked
  nucleotides
• Double stranded helix
• Twisted ladder
• Determines traits of EVERY LIVING ORGANISM

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Nucleotide Structure

• 3 parts
• Sugar (deoxyribose or ribose)
• Phosphate (P with oxygens attached)
• Nitrogen base
• Adenine
• Thymine
• Guanine
• Cytosine

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Nucleotide Structure

• 2 classes of nucleotides
• Purines
• Adenine
• Guanine
• Pyrimidines
• Thymine
• Guanine

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Nitrogen Base Pairing

• Adenine Thymine
• 4-eva
• Guanine Cytosine

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Nitrogen Base Pairing

• Adenine Thymine
• Guanine Cytosine

Hydrogen Bond
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Nitrogen Base Pairing
Hydrogen Bond

• Adenine Thymine
• Cytosine Guanine
• Thymine Adenine
• Cytosine Guanine
• Cytosine Guanine
• Adenine Thymine
• Guanine Cytosine

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Nitrogen Base Pairing

• Adenine Thymine
• Cytosine Guanine
• Thymine Adenine
• Cytosine Guanine
• Cytosine Guanine
• Adenine Thymine
• Guanine Cytosine

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• 3?5
• Each Strand has Opposite Orientations
• 5?3

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• Compl-e-ment complement
• To complete, finish, or fill something up
• NOT this kind
• Compl-i-ment - compliment
• You are the coolest student on this planet!

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What is the COMPLEMENTARY DNA STRAND?

• EXAMPLE 1
• 3 end 5 end
• ATTGACCATTGATAGCCGAATA
• TAACTGGTAACTATCGGCTTAT
• EXAMPLE 2
• 5 end 3 end
• TCTTCGGAACATTAGTCGAGGC
• AGAAGCCTTGTAATCAGCTCCG

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The Cs of Genetics
CHROMATIN
DNA ladder
DNA double helix
Histones (proteins) with DNA coiled around them
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CHROMATID
DNA ladder
DNA double helix
Chromatin
2 Chromatids
Coiled up Chromatin
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CHROMOSOME
Chromatin
2 Chromatids
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Centromere
Centromere Holds sister chromatids together in a
chromosome